scholarly journals Urine Metabolites for Estimating Daily Intake of Nicotine From Cigarette Smoking

2019 ◽  
Vol 22 (2) ◽  
pp. 288-292 ◽  
Author(s):  
Neal L Benowitz ◽  
Gideon St. Helen ◽  
Natalie Nardone ◽  
Lisa Sanderson Cox ◽  
Peyton Jacob
Keyword(s):  
Daily Intake ◽  
Cost Effective ◽  
Nicotine Exposure ◽  
Strongly Correlated ◽  
Urine Metabolites ◽  
Nicotine Intake ◽  
The Impact ◽  
Slow Metabolizers ◽  
Selection Of ◽  
Research Studies

Abstract Introduction Accurate measurement of nicotine exposure from cigarette smoke is important in studying disease risk and level of dependence. Urine total nicotine equivalents, the molar sum of nicotine and six metabolites (NE7), accounts for more than 90% of a nicotine dose and is independent of individual metabolic differences. However, measuring NE7 is technically difficult and costly. We compared NE7, the gold standard of nicotine intake, with different combinations of fewer urinary nicotine metabolites. We also examined the impact of individual differences in nicotine metabolic rate, sex, and race on strength of association with NE7. Methods Urine samples from 796 daily smokers, who participated across five clinical studies, were assayed for nicotine and/or metabolites. Associations with NE7 were assessed by regression and Bland–Altman analyses. Results Overall, the molar sum of urine [cotinine + 3′-hydroxycotinine (3HC)] (NE2) and [nicotine + 
cotinine + 3HC] (NE3) were strongly correlated with NE7 (r = .97 and .99, respectively). However, in slow metabolizers NE2 was less predictive of NE7, whereas NE3 was equally robust. Urine total cotinine was also strongly correlated with NE7 (r = .87). Conclusions Urine NE3 is a robust biomarker of daily nicotine intake, independently of individual metabolic differences, whereas NE2 is less accurate in slow metabolizers. Our findings inform the selection of more rigorous and cost-effective measures to assess nicotine exposure in tobacco research studies. Implications The molar sum of urine total nicotine, cotinine and 3HC (NE3) is a robust biomarker of daily nicotine intake, independently of individual metabolic differences, and performs as well as measuring seven nicotine metabolites (NE7). The sum of cotinine and 3HC (NE2) is less accurate in slow metabolizers. Our findings inform the selection of more rigorous and cost-effective measures to assess nicotine exposure in tobacco research studies.

Quantitative Selection of Variation Reduction Plans

1998 ◽  
Author(s):  
Anna C. Thornton
Keyword(s):  
Risk Mitigation ◽  
Cost Effective ◽  
Variation Reduction ◽  
Multiple Quality Characteristics ◽  
Cost Effective Approach ◽  
Manufacturing Performance ◽  
The Impact ◽  
Manufacturing Variation ◽  
Selection Of

Abstract Quality has been a rallying call in the design and manufacturing world for the last two decades. One way to improve quality is to reduce the impact of manufacturing variation. Variation risk mitigation is challenging especially when a product has multiple quality characteristics and complex production and assembly. It is common wisdom that companies should identify and mitigate the risk associated with variation throughout the design process. As yield problems are identified, they should be mitigated using the most cost effective approach. One approach to variation risk mitigation is variation reduction (VR). VR targets reduction of variation introduced by existing manufacturing processes using tools such as Design of Experiments (DOE) and robust design. Many companies have specialized groups that specialize in these methods. VR teams have the role of improving manufacturing performance; however, these teams are limited in their resources. In addition, no tools exist to quantitatively determine where a VR team’s efforts are most effectively deployed. This paper provides a mathematical and optimization model to best allocate VR resources in a complex product.

scholarly journals Improvement of the Impact Properties of Composite Laminates by Means of Nano-Modification of the Matrix—A Review

2018 ◽  
Vol 8 (12) ◽  
pp. 2406 ◽  
Author(s):  
Hamed Saghafi ◽  
Mohamad Fotouhi ◽  
Giangiacomo Minak
Keyword(s):  
Composite Laminates ◽  
Cost Effective ◽  
Careful Consideration ◽  
Impact Performance ◽  
Compression After Impact ◽  
The Matrix ◽  
The Right ◽  
2D And 3D ◽  
The Impact ◽  
Selection Of

This paper reviews recent works on the application of nanofibers and nanoparticle reinforcements to enhance the interlaminar fracture toughness, to reduce the impact induced damage and to improve the compression after impact performance of fiber reinforced composites with brittle thermosetting resins. The nanofibers have been mainly used as mats embedded between plies of laminated composites, whereas the nanoparticles have been used in 0D, 1D, 2D, and 3D dimensional patterns to reinforce the matrix and consequently the composite. The reinforcement mechanisms are presented, and a comparison is done between the different papers in the literature. This review shows that in order to have an efficient reinforcement effect, careful consideration is required in the manufacturing, materials selection and reinforcement content and percentage. The selection of the right parameters can provide a tough and impact resistant composite with cost effective reinforcements.

scholarly journals Selecting Bolt-on Dimensions for the EQ-5D: Testing the Impact of Hearing, Sleep, Cognition, Energy, and Relationships on Preferences Using Pairwise Choices

2020 ◽  
Vol 41 (1) ◽  
pp. 89-99
Author(s):  
Aureliano Paolo Finch ◽  
John Brazier ◽  
Clara Mukuria
Keyword(s):  
Online Survey ◽  
Logistic Models ◽  
Cost Effective ◽  
Health State ◽  
Health States ◽  
Cost Effective Approach ◽  
Level 3 ◽  
Severity Levels ◽  
The Impact ◽  
Selection Of

Background Generic preference-based measures (GPBMs) such as the EQ-5D are valid across many conditions, but in some cases, “bolting on” additional dimensions may improve validity. The selection of “bolt-ons” has been based on the psychometric impact of individual dimensions, but preferences provide another important way to select them. This study aims to test the potential of using pairwise choices to inform the selection of bolt-ons for the EQ-5D-5L. Methods General population preferences were collected using an online survey of 1040 UK residents. Three EQ-5D-5L health state pairs were selected based on pairs that had a 50:50 split in respondent preferences from a previous pairwise survey. Participants were presented with pairwise choices of EQ-5D-5L health states without and with bolt-ons of hearing, sleep, cognition, energy, and relationships, each added individually. Logistic models were used to assess the impact of bolt-ons, as well as bolt-ons at different severity levels, on the log odds of responders choosing between health states. Results Preferences varied according to the bolt-ons and their severity level (only levels 1, 3, and 5 were used). Additions of bolt-ons at level 1 generally resulted in nonstatistically significant differences while additions of bolt-ons at level 3 and level 5 produced a negative and statistically significant impact on preferences for the health state with the bolt-on. At level 5, hearing had the largest impact, followed by cognition, relationships, energy, and sleep. At level 3, cognition produced the largest impact, followed by hearing and sleep with similar impacts, energy, and relationships. This ordering offers information for bolt-on selection, with hearing and cognition appearing as the most important. The weight placed on the different health problems is not constant across severity levels between bolt-ons. Conclusions Pairwise choices provide a cost-effective approach of generating information on preferences to support bolt-on selection.

scholarly journals Locating microseismic sources with a single seismometer channel using coda wave interferometry

Geophysics ◽  
2017 ◽  
Vol 82 (3) ◽  
pp. A19-A24 ◽  
Author(s):  
Youqian Zhao ◽  
Andrew Curtis ◽  
Brian Baptie
Keyword(s):  
Single Channel ◽  
Cost Effective ◽  
Coda Wave ◽  
Probabilistic Framework ◽  
Data Set ◽  
Cost Effective Method ◽  
Potential Applications ◽  
The Impact ◽  
Coda Wave Interferometry ◽  
Selection Of

A novel source location method based on coda wave interferometry (CWI) was applied to a microseismic data set of mining-induced events recorded in Nottinghamshire, England. CWI uses scattered waves in the coda of seismograms to estimate the differences between two seismic states. We used CWI to estimate the distances between pairs of earthquake locations, which are then used jointly to determine the relative location of a cluster of events using a probabilistic framework. We evaluated two improvements to this location technique: These account for the impact of a large difference in the dominant wavelength of a recording made on different instruments, and they standardize the selection of parameters to be used when implementing the method. Although the method has been shown to produce reasonable estimates on larger earthquakes, we tested the method for microseismic events with shorter distinguishable codas in recorded waveforms, and hence, fewer recorded scattered waves. The earthquake location results are highly consistent when using different individual seismometer channels, showing that it is possible to locate event clusters with a single-channel seismometer. We thus extend the potential applications of this cost-effective method to seismic events over a wider range of magnitudes.

scholarly journals 177 The effect of breeding system on voluntary forage consumption of beef cows

2019 ◽  
Vol 97 (Supplement_1) ◽  
pp. 65-65
Author(s):  
Claire Andresen ◽  
Amanda Holder ◽  
Megan Gross ◽  
Aksel Wiseman ◽  
Adam McGee ◽  
...  
Keyword(s):  
Breeding System ◽  
Daily Intake ◽  
Beef Cows ◽  
Crossbred Cattle ◽  
Feeding Trial ◽  
Forage Intake ◽  
Maintenance Requirements ◽  
The Impact ◽  
Selection Of ◽  
Genetic Trends

Abstract Recent genetic trends in beef breeds suggest an imbalance in the selection of output and input traits. The inverse relationship between cow maintenance requirements with output traits such as growth and milk production may have ramifications on carrying costs of cows as well as feed intake of the cow herd. One method commonly used to maximize efficiency within a production system is to utilize a crossbreeding system to capitalize on breed complementarity. The objective of this study was to investigate the impact of breeding system on forage intake and determine correlations between breeding system, dry matter intake, and maintenance requirements of beef cows. To do this, a 45-d feeding trial was conducted using 59 pregnant, non-lactating Angus (ANG; n = 32) and Hereford x Angus (HA; n = 27) cows similar in mature BW, growth, and milk potential. Animals were assigned to pen based on breed with four pen replicates per breed. Cows were housed in dry-lot pens equipped with shade, windbreaks, and feed bunks with free-choice access to clean water. A chopped hay ration (65% DM, 55.7% TDN, 7.8% CP) was provided ad libitum to determine forage intake. Daily intake tended to be lower (P = 0.06) for HA compared to ANG (134.25 g/kg MBW ANG; 125.37 g/kg MBW HA). There was no difference in BW at initiation or conclusion of the trial, however, HA sustained greater BCS throughout the duration of the study (P > 0.01). After accounting for differences in retained energy, there were no detectable differences in maintenance requirements (P = 0.11). Results of this study suggest lower forage intake of crossbred cattle and suggests potential differences in energy prioritization and partitioning between breeds.

Tools and Methods for Internal Pipe Coating Evaluation for Gas Transmission Systems

2012 ◽  
Author(s):  
K. K. Botros ◽  
M. Piazza ◽  
D. Abayarathna
Keyword(s):  
Life Cycle Cost ◽  
Cost Effective ◽  
Sound Design ◽  
Pressure Losses ◽  
Pipeline Systems ◽  
Consistent Manner ◽  
Transmission Pipeline ◽  
And Performance ◽  
The Impact ◽  
Selection Of

The option of internally coating a new pipeline, or a section of an existing pipeline has emerged in recent years as competition in the energy marketplace grows more intense and coating technologies have advanced from 100% solvent-base to 100% dry-based. Internally coated pipes would mean additional capital cost, but will result in lower pressure losses, hence lower compression power, lower fuel consumption and lower emission. Therefore, there is a trade-off that needs to be assessed, which is the subject of the present paper. The present paper first provides a proposed standardized method to report the internal wall roughness parameters that could be used to compare bare vs. different coating technologies in a consistent manner. The second part of the paper focuses on evaluating the impact and performance of internal coatings on flow efficiency in energy transmission pipeline systems. A tool and methods were developed to evaluate all of the various options specific to internal pipe coating (including bare pipe option) using a Life Cycle Cost (LCC) economic tool developed for this purpose. The incremental Cumulative Present Value Cost of Service (iCPVCOS) associated with the application of the various coating technologies, as well as quantification of the relative benefits of each compared to a bare pipe, are the main outcome of the tool. This provides an impetus to sound design and selection of the most cost effective technology for internally coating the pipes, whether for new or existing pipeline systems. Examples of various scenarios involving a 2900 km pipeline coated using different internal coating technologies are discussed.

Effect of Polyester Mooring Stiffness on SCR Design for FPSO Application

2012 ◽  
Author(s):  
Gwo-Ang Chang ◽  
Pao-Lin Tan ◽  
Ken Huang ◽  
Tom Kwan
Keyword(s):  
Global Analysis ◽  
Dynamic Stiffness ◽  
Cost Effective ◽  
Systematic Investigation ◽  
Steel Catenary Riser ◽  
Motion Responses ◽  
Stiffness Model ◽  
Riser Design ◽  
The Impact ◽  
Selection Of

Polyester rope is a visco-elastic material and its stiffness is affected by mean tension, tension amplitude, loading period, and loading history. Qualitatively it may be felt that rope stiffness significantly affects vessel offset, which in turn affects riser performance and cost. However, a systematic investigation of the impact of rope stiffness on riser stress and fatigue life has not been published for a wide variety of design conditions. This paper describes such a study, and provides specific guidance to designers for the prudent selection of a rope stiffness model and values to achieve safe and cost effective riser design. This study investigated the effect of polyester rope stiffness on steel catenary riser (SCR) design for an FPSO sited in a variety of water depths considering environmental conditions representative of West Africa. Static/dynamic stiffness models for polyester rope in the recently issued ABS Guidance Notes on the Application of Fiber Rope for Offshore Mooring [1] were used in a global analysis to provide motion responses for the riser analysis. Time domain riser analysis was performed to obtain maximum riser stress and fatigue damage under various conditions. Based on the results of the investigation of riser and mooring analysis, guidance on the impact of rope stiffness to the riser design has been developed.

scholarly journals 1 The effect of breeding system on voluntary forage consumption of beef cows

2019 ◽  
Vol 97 (Supplement_1) ◽  
pp. 16-16
Author(s):  
Claire Andresen ◽  
Amanda Holder ◽  
Megan Gross ◽  
Aksel Wiseman ◽  
Adam McGee ◽  
...  
Keyword(s):  
Breeding System ◽  
Daily Intake ◽  
Beef Cows ◽  
Crossbred Cattle ◽  
Feeding Trial ◽  
Forage Intake ◽  
Maintenance Requirements ◽  
The Impact ◽  
Selection Of ◽  
Genetic Trends

Abstract Recent genetic trends in beef breeds suggest an imbalance in the selection of output and input traits. The inverse relationship between cow maintenance requirements with output traits such as growth and milk production may have ramifications on carrying costs of cows as well as feed intake of the cow herd. One method commonly used to maximize efficiency within a production system is to utilize a crossbreeding system to capitalize on breed complementarity. The objective of this study was to investigate the impact of breeding system on forage intake and determine correlations between breeding system, dry matter intake, and maintenance requirements of beef cows. To do this, a 45-d feeding trial was conducted using 59 pregnant, non-lactating Angus (ANG; n = 32) and Hereford x Angus (HA; n = 27) cows similar in mature BW, growth, and milk potential. Animals were assigned to pen based on breed with four pen replicates per breed. Cows were housed in dry-lot pens equipped with shade, windbreaks, and feed bunks with free-choice access to clean water. A chopped hay ration (65% DM, 55.7% TDN, 7.8% CP) was provided ad libitum to determine forage intake. Daily intake tended to be lower (P = 0.06) for HA compared to ANG (134.25 g/kg MBW ANG; 125.37 g/kg MBW HA). There was no difference in BW at initiation or conclusion of the trial, however, HA sustained greater BCS throughout the duration of the study (P > 0.01). After accounting for differences in retained energy, there was no detectable differences in maintenance requirements (P = 0.11). Results of this study suggest lower forage intake of crossbred cattle and suggests potential differences in energy prioritization and partitioning between breeds.

Methods for Restricting Maximum Exposure Rate in Computerized Adaptative Testing

Methodology ◽  
2007 ◽  
Vol 3 (1) ◽  
pp. 14-23 ◽  
Author(s):  
Juan Ramon Barrada ◽  
Julio Olea ◽  
Vicente Ponsoda
Keyword(s):  
Measurement Accuracy ◽  
Computerized Adaptive Testing ◽  
Computation Time ◽  
Adaptive Testing ◽  
Exposure Rate ◽  
Control Parameters ◽  
The Impact ◽  
Two Alternatives ◽  
Selection Of ◽  
Maximum Exposure

Abstract. The Sympson-Hetter (1985) method provides a means of controlling maximum exposure rate of items in Computerized Adaptive Testing. Through a series of simulations, control parameters are set that mark the probability of administration of an item on being selected. This method presents two main problems: it requires a long computation time for calculating the parameters and the maximum exposure rate is slightly above the fixed limit. Van der Linden (2003) presented two alternatives which appear to solve both of the problems. The impact of these methods in the measurement accuracy has not been tested yet. We show how these methods over-restrict the exposure of some highly discriminating items and, thus, the accuracy is decreased. It also shown that, when the desired maximum exposure rate is near the minimum possible value, these methods offer an empirical maximum exposure rate clearly above the goal. A new method, based on the initial estimation of the probability of administration and the probability of selection of the items with the restricted method ( Revuelta & Ponsoda, 1998 ), is presented in this paper. It can be used with the Sympson-Hetter method and with the two van der Linden's methods. This option, when used with Sympson-Hetter, speeds the convergence of the control parameters without decreasing the accuracy.

Medical Literature Searches -How Many Bibliographic Databases are Needed for Sufficient Retrieval in Medical Topics?

1985 ◽  
Vol 24 (03) ◽  
pp. 163-165 ◽  
Author(s):  
K. John
Keyword(s):  
Medical Literature ◽  
Cost Effective ◽  
Medical Faculty ◽  
Bibliographic Databases ◽  
Literature Searches ◽  
Selection Of

SummaryAs many bibliographic services in medicine are offered, literature searches in eight databases at DIMDI were performed to find out which database is most important in medicine. The distribution of publications from members of the medical faculty of Frankfurt University was examined. No save prediction is possible as to which database will yield most articles. Overlapping from different databases is often rather low. The selection of an appropriate database mix for sufficient recall and in a cost-effective manner.is a task for an experienced searcher.

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